This invention relates to a container in which a cover is coupled by hinges with a container body for simplifying the assembling of the cover with the body and assuring the sealing effect of the cover to the body.
A hinge structure in which a coiled spring is engaged with a hinge shaft has been heretofore employed as means for coupling a cover with a container body in some of the conventional containers.
In such a structure, the coiled spring is elastically contacted at one end thereof with part of the cover and at the other end thereof with part of the container body. The cover is opened from the body by the elastic force of the coiled spring in a circumferential direction when the cover is unlocked by a predetermined operation from a state in which the cover is locked on the container body.
However, in this structure, a hinge shaft should be inserted into shaft holes perforated at the cover and the container body while respectively locking the both ends of the coiled spring to the parts of the cover and the body. In addition, the hinge shaft should also be simultaneously inserted into the hole of the coiled spring. It is accordingly difficult to insert the hinge shaft while applying a resisting force against the elastic force of the coiled spring having the elastic force in the circumferential direction, and it is remarkably hard and complicated to position and insert the hinge shaft to the holes of the cover and the body as well as the coiled spring.
Further, in the container of the hinge structure described above, the cover should be constructed so that the hinge shaft must be rotated as a shaft. Therefore, if the cover and the container body are not associated in a predetermined margin, the cover cannot smoothly rotate with respect to the container body in opening and closing operations. As a result, a gap has to be formed between the cover and the container body. Consequently, it lacks the sealability between the cover and the body.
Therefore, in the conventional container having a tight sealability, the hinge coupling for opening and closing of the cover in the container cannot be employed between the cover and the container body; and a plug shape structure is engaged separately from the cap, for example, threaded to the container body. Such a conventional container is complicated to open and close the cover of the container body.